RE: [PATCH] PCI: hv: Detect and fix Hyper-V PCI domain number collision

From: Dexuan Cui
Date: Wed May 22 2019 - 01:17:27 EST


> From: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>
> Sent: Tuesday, May 21, 2019 9:40 PM
>
> Thanks for working this out with the host team.
> Now if we could just get some persistent slot information it would make udev in systemd happy.

The slot info comes from the serial number "hpdev->desc.ser", which may not guarantee
uniqueness: "...Hyper-V doesn't provide unique serial numbers": see the changelog of the below
commit:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=29927dfb7f69bcf2ae7fd1cda10997e646a5189c

And we can pass through multiple devices to a VM in any order (i.e. hot add/remove), so IMO
the "slot" info is not unique and persistent.

Thanks,
-- Dexuan